Weed and algae killer



United States Patent, O

3,494,758 WEED AND ALGAE KILLER Erwin Otto Kopp and Karl Leonhard Milles, Munich,

Bavaria, Germany, assignors to Consortium fur Elektrochemische Industrie G.m.b.I-I., Munich, Bavaria, Germany, a German corporation No Drawing. Filed Mar. 7, 1967, Ser. No. 621,137 Claims' priority, applicltiosn Germany, Mar. 9, 1966, 3 4

Int. Cl. A01n 9/12, 9 22, 23/00 U.S. Cl.' '7167 1 Claim ABSTRACT OF THE DISCLOSURE This invention relates to weed and algae killers and it has for its object to provide a novel and highly effective selective. preparation of this type. Specifically, :the invention comprises a weed and algae kill'er containing 2- thiolthiazol (Z-merkaptothiazol) as the active ingredient.

BACKGROUND OF THE INVENTION Our Weed and algae killer, containing 2-thi0lthiazol as the active ingredient, is highly selective. It is useful, for instance, for killing weeds in grain crops. Water plants can also be controlled. For instance, dosages of 25-30 p.p.m. (parts per million) of Z-thiolthiazol are suflicient for water lentils (duckweed). Within this concentration a destruction of chlorophyll also takes place within 6 to 21 days. i

The algostatic effect of 2-thiolthiazol on Chlorella vulgaris amounts to p.p.m. Depending on the species of algae, 25-50 p.p.m. is sufiicient for an algicide effect. When attacking algae and weeds in water it is important that even at 50 p.p.m. there should be no toxicity to fish life. Z-thiolthiazol is water soluble, which makes its application easier. Depending on the manner of use and the given requirements, one can add to the preparation adhesiveand/or wetting agents, dispersion agents, other active substances and additives, fertilizers, floating agents diluting agents, etc.

DESCRIPTION OF PREFERRED EMBODIMENTS The invention is illustrated by the following examples. The preparations and the definitions 18 shown in the tables consisting of the following:

50 parts 2-th1o1th1azol 50 parts diethylene glycol monoethyl ether 2-thiolthiazol Patented Feb. 10, 1970 "flee 50 parts 2-thiolthiazol 45 parts urea 5 parts polyvinyl alcohol parts Z-thiolthiazol 20 parts pentachlorphenol Sodium pentachlorphenol as a comparison agent A quaternary ammonium compound with an algicide effect as a comparison agent.

EXAMPLE 1 Herbicide tests 0=no effect l0=plant died completely (a) Cornflower, second leaf Temperature C.)-

Kg./hectare &

3 days 7 days 14 days Preparatmn as spray hquor/ described eotare 5 2O 5 20 5 20 -1 4 kg. /600/1 3 1O 10 10 l0 l0 4 kg.'/600/1 3 10 9-10 10 10 10 4 kg'J/600/1 1 8 9 10 1O 10 No.4 4 kgglfioo/l 9 10 No.5 4kg./600/1 2 910 10 Temperature C.)

Kg./hectare &

3 days 7 days 14 days Preparation as spray hquor/ described hectare 5 20 5 2O 5 2O Galinsolga, fourth leaf Temperature C.)

KgJhectare & 3 days 7 days 14 days Preparation as spray liquor/ described hectare 20 5 20 5 20 No. 6 4kg./600/1 8 10 10 Winter wheat, 3rd leaf Temperature C.)

4 KgJhectare dz 3 days 7 days 14 days Preparatlon as spray llquor/ described hectare 5 20 5 20 5 20 No. 1 4 kgL/tSOO/l 1 1 1 No 2 4kg./600/l 0 0 1 0 0 0 No 3 4 kg./600/1 0 1 1-2 3 3 3 No. 4 4 kg./600/1 1 1 4 3 3 3 No. 5 4 kg./60(l/1 1 0 0 4 0 (e) Hair grass, 10 cm. high Temperature C.)

Kgvlhectare & 3 days 7 days 14 days Preparation as spray llquor/ described hectare 20 5 20 5 20 No. 4 20 kg./600/1 3 3 3 No. 5 20 kg ./600/1 1 2 2 Examples (d) and (e) above show that even under high EXAMPLE 3 dosages there is little damage to gramlnaceae- Cholorella vulgizris.Alg'ostatic and algicide effect algostatic efiect aiteralgicide effect after- Preparation days, days, days, days, days, days,

as described p.p.m. p.p.m. p.p.m. p.p.m. p.p .m. p.p.m.

After 8 days After 14 days Chicliweed (Stellaria media) 9 9 Catchweed (Galium apan'ne) 1 9 Ivy-leafed Speedwell (Verom'c hederaefolia) 10 10 EXAMPLE 2 The invention claimed is:

1. Method of combating weeds and algae which com- Chlomphyl reduction on duckweed (Lemma) prises applying to. said weeds and algae an effective =noreduction amount of 2-thiolthiazol. 10=complete reduction (discoloration) Reduction 10 p.p.m. Reduction 25 p.p.m.

after after after after Preparation as described 14 days 21 days 14 days 21 days No. 1 4 6 9 9-10 N0. 2 8 10 10 10 No. 8 for comparison 2 3 5 5 JAMES O. THOMAS, JR., Primary Examiner U.S. Cl. X.R. 71-90 

